Electrical boxes are commonly mounted to a stud or other support structure for supporting an electrical device and enclosing electrical wiring. The electrical boxes are often mounted in a variety of positions and locations in the wall or ceiling.
Portable electrical junction boxes typically are attached to an electrical cable or cord such that the boxes can be moved to a suitable location during use. The portable electrical boxes are particularly suitable for construction sites where electrical power is needed in different locations and can be moved to different locations as needed during work. The portable electrical junction box generally provides an electrical receptacle to provide electrical power to tools, lights and the like. During use, particularly on construction sites, the portable electrical junction boxes are subjected to physical abuse which can result in damage to the box.
Various electrical boxes have been developed for numerous purposes. One example is disclosed in U.S. Pat. No. 3,724,706 to Slocum which discloses an explosion proof junction box having a cap and a body portion. The body portion forms the junction box as a one piece molded structure. The body portion and cap are provided with an outer layer formed from a polymeric material such as polyvinyl chloride. The outer layer is formed with flexible flanges for forming a seal between the cap and the body portion.
Another example is disclosed in U.S. Pat. No. 5,621,189 to Dodds which discloses a conduit and a cover. The outer surfaces of the cover and the body are coated with a corrosion resistant polymeric material. The coating is disclosed as being a flexible, durable impact resistant polymer such as polyvinyl chloride.
U.S. Pat. No. 4,134,636 to Kleinatland et al. discloses an electrical outlet box with recesses on the outer surface and opening in a flange for receiving screws. The box includes an interior sleeve for telescopic engagement with the box.
U.S. Pat. No. 6,820,760 to Wegner et al. discloses an electrical outlet box extension having an interior sleeve with a plurality of ribs along its exterior surface. The interior sleeve also includes a plurality of fastening brackets for fixedly attaching the interior sleeve to an exterior ring. The exterior ring is attached to an electrical box.
U.S. Pat. No. 2,373,861 to Brown discloses an electrical box extension that slides within the opening of the electrical box. The upper surface of the box includes inwardly extending flanges with an opening for receiving screws to adjust the position of the sleeve.
Other electrical boxes are also disclosed in U.S. Pat. Nos. 2,378,861 to Peevey, U.S. Pat. No. 2,867,349 to Parker Jr., U.S. Pat. No. 3,684,819 to Wilson, U.S. Pat. No. 4,408,695 to Balkwill et al., U.S. Pat. No. 4,884,715 to Pohlmann, U.S. Pat. No. 7,038,129 to Fox and U.S. Pat. No. 6,974,295 to Anderson.
While each of the prior devices has been generally suitable for the intended purpose, there is a continuing need in the industry for an improved portable electrical box.